24 research outputs found

    3D model

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    Tato práce se zabývá problematikou rekonstrukce trojrozměrné scény ze sekvence sníkmů záznamu z obyčejné kamery. První část práce popisuje principy vyžívané při řešení úlohy, druhá část popisuje algoritmus rekonstrukce a jeho implementaci v jazyce Python. Tento program je dále demonstrován na několika vybraných scénách. Závěr diskutuje o kvalitě vytvořených modelů, nedostatcích programu a možných vylepšeních.This paper concerns the task three-dimensional scene using image sequence obtained with an ordinry camera. First portion of this thesis outlines the principles used in solving of the task, the second chapter describes a reconstucion algorithm and it's implementation in the Python programming language. The output of this program is demonstrated on several selected scenes. Final remarks discuss the quality of resulting models, shortcomings of the program and possible improvements.

    The role of individual traits in the Northern Lapwing (Vanellus vanellus) females on breeding performance, mating status and male incubation effort

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    Role ornamentace opeření a dalších individuálních vlastností v pohlavím výběru je u ptáků široce studovanou problematikou. Drtivá většina prací se ovšem zabývá významem ornamentace samců a samičími preferencemi při jejich výběru. Recentní poznatky ovšem ukazují, že podobně širokou škálu adaptací lze nalézt, zaměříme-li se na signální význam opeření samičího. Tato práce zkoumá potenciální význam melaninové ornamentace a dalších individuálních vlastností pro průběh hnízdního procesu u samic čejky chocholaté (Vanellus vanellus), známého a široce rozšířeného polygynního bahňáka zemědělské krajiny. Žádná ze studovaných charakteristik nesignalizovala investici do reprodukce prostřednictvím objemu vajec ve snůšce. Samice s delším křídlem, větším rozsahem předhnízdního pelichání loketních letek a větším rozsahem melaninové ornamentace ovšem začínaly hnízdit, poněkud překvapivě, později v sezoně. I přesto se ornamentace samic ukazuje jako pravděpodobně samci preferovaný znak, protože v průměru inkubovali více na hnízdech samic s výraznější ornamentací. Stejně tak inkubovali výrazněji v pozdních fázích inkubační periody. Žádný vliv na množství samčí inkubační péče naopak nebyl zjištěn u velikosti vajec, či načasování hnízda v rámci sezony. Podobně ani velikost hnízdního uskupení, coby ukazatel možnosti...Feather ornaments and its role as a signals in sexual selection has been broadly studied topic in avian biology. However, vast majority of studies focus especially on role of male ornamentation and female preferences in sexual selection. Despite this fact, recent work shows, that similar palette of adaptive functions can be found for female feather ornaments, and male preferences for them, respectively. This study focuses on possible importance of female melanin-based ornaments and other individual on breeding performance in the Northern Lapwing (Vanellus vanellus), common polygynous wader breeding in agricultural landscape. No significant predictor of female investment to egg size was found. Long winged females with bigger proportion of secondaries changed during prenuptial moulting and bigger extent of melanin ornaments tended, surprisingly, to later timing of breeding. Contrary to this trend, extent of female ornamentation seems to be sexually selected trait by males. Analysis of male incubation behavior shows, that males incubate more in nests of more ornamented females, as well as in nests in later incubation stage. These findings seems to be in a good agreement with "Differential allocation hypothesis". On the other site, no effect of clutch egg sizes and timing of breeding was found....Katedra ekologieDepartment of EcologyPřírodovědecká fakultaFaculty of Scienc

    3D reconstruction from multiple views

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    Tato práce se zabývá rekonstrukcí trojrozměrného modelu statické scény z několika snímků. Předpokládá se při tom znalost intrinsických parametrů použitých kamer. V teoretické části jsou popsány základní principy jednotlivých kroků rekonstrukce. Dále jsou popsány různé možnosti implementace datového modelu vhodného pro tuto úlohu a jejich výhody i nevýhody. Praktická část se dále zabývá srovnáním různých metod filtrování nesprávně určených dvojic korespondujících klíčových bodů, implementací algoritmu polární stereo rektifikace a porovnáním různých způsobů výpočtu mapy disparity pomocí knihovny OpenCV. Na závěr jsou uvedeny a diskutovány ukázky zrekonstruovaných 3D modelů.This thesis deals with the task of three-dimensional scene reconstruction using image data obtained from multiple views. It is assumed that intrinsic parameters of the utilized cameras are known. The theoretical chapters describe the basic priciples of individual reconstruction steps. Variuous possible implementaions of data model suitable for this task are also described. The practical part also includes a comparison of false keypoint correspondence filtering, implementation of polar stereo rectification and comparison of disparity map calculation methods that are bundled with the OpenCV library. In the final portion of the thesis, examples of reconstructed 3D models are presented and discussed.

    The role of individual traits in the Northern Lapwing (Vanellus vanellus) females on breeding performance, mating status and male incubation effort

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    Feather ornaments and its role as a signals in sexual selection has been broadly studied topic in avian biology. However, vast majority of studies focus especially on role of male ornamentation and female preferences in sexual selection. Despite this fact, recent work shows, that similar palette of adaptive functions can be found for female feather ornaments, and male preferences for them, respectively. This study focuses on possible importance of female melanin-based ornaments and other individual on breeding performance in the Northern Lapwing (Vanellus vanellus), common polygynous wader breeding in agricultural landscape. No significant predictor of female investment to egg size was found. Long winged females with bigger proportion of secondaries changed during prenuptial moulting and bigger extent of melanin ornaments tended, surprisingly, to later timing of breeding. Contrary to this trend, extent of female ornamentation seems to be sexually selected trait by males. Analysis of male incubation behavior shows, that males incubate more in nests of more ornamented females, as well as in nests in later incubation stage. These findings seems to be in a good agreement with "Differential allocation hypothesis". On the other site, no effect of clutch egg sizes and timing of breeding was found...

    The role of individual traits in the Northern Lapwing (Vanellus vanellus) females on breeding performance, mating status and male incubation effort

    Get PDF
    Feather ornaments and its role as a signals in sexual selection has been broadly studied topic in avian biology. However, vast majority of studies focus especially on role of male ornamentation and female preferences in sexual selection. Despite this fact, recent work shows, that similar palette of adaptive functions can be found for female feather ornaments, and male preferences for them, respectively. This study focuses on possible importance of female melanin-based ornaments and other individual on breeding performance in the Northern Lapwing (Vanellus vanellus), common polygynous wader breeding in agricultural landscape. No significant predictor of female investment to egg size was found. Long winged females with bigger proportion of secondaries changed during prenuptial moulting and bigger extent of melanin ornaments tended, surprisingly, to later timing of breeding. Contrary to this trend, extent of female ornamentation seems to be sexually selected trait by males. Analysis of male incubation behavior shows, that males incubate more in nests of more ornamented females, as well as in nests in later incubation stage. These findings seems to be in a good agreement with "Differential allocation hypothesis". On the other site, no effect of clutch egg sizes and timing of breeding was found...
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